In large cities, different public transportation services are offered to users: trains, subways, trams, buses, etc.
These services are managed independently of one another, most often by different operators.
In this document, a monomodal network is a network on which vehicles belonging to a single mode of transportation travel: for example the subway, bus, tram, train. The operator of a monomodal network sees to service on this monomodal network based on a transportation plan, i.e., a plan for serving stops, associated with a timetable or passage frequency. An operator often manages a set of monomodal networks with no effective synchronization between them.
In general, a monomodal network is characterized by the existence of a centralized operating system making it possible to manage traffic on the corresponding monomodal network. An operating system uses timetables to control the movement of each vehicle traveling on the monomodal network. A timetable defines the departure times from each station on the line, the normal travel times between two stations on the line, the normal parking times, etc. A timetable is updated dynamically during the travel of the corresponding vehicle with operating information, for example the interval with the vehicle preceding the vehicle in question, the time necessary to transfer users during a stop at the station, etc.
A multimodal land transportation network is, by definition, a network that groups together different monomodal networks and allows the user to go from a departure station to an arrival station using one or several public transportation services.
However, in such a multimodal network, it is difficult for a user to minimize his travel time between a departure station and an arrival station effectively, in particular when this journey includes a transfer between two services; i.e., a station allowing a user to exit a first vehicle serving a first line of a first monomodal network to enter a second vehicle serving a second line of a second monomodal network.
The user can for example try to plan his trip by querying a database aggregating the theoretical schedules for the different services. However, the services being managed independently, the theoretical schedules are not correlated and may lead to an extended wait time in the transfer station.
Furthermore, the theoretical schedules are difficult to respect, such that during the trip, if the first vehicle is late, the second vehicle may have left the transfer station before the first vehicle has arrived. Consequently, the user misses his transfer and is required to wait for the next vehicle serving the second line or to redefine his trip. The frequency of vehicles on certain lines being low, the wait time for the user may be substantial.
Therefore, even when he has optimized his trip, the user is required to take a trip with an extended duration. The quality of service perceived by the user is therefore not optimal.
To avoid this type of situation caused by independently-managed transportation services, there is therefore a need to supervise the operation of the multimodal transportation network.